1. Field of the Invention
The present invention relates to a kit for separating and purifying nucleic acids or a variety of biological materials and a system for automatically performing the operations of separating and purifying a variety of biological materials using the kit.
2. Description of the Prior Art
Machines for separating and purifying nucleic acids or biological materials from blood or other biological samples have been widely used in a variety of fields such as biology, biochemistry, molecular medicine, forensic medicine, medical diagnostics, etc.
Recently, Polymerase Chain Reaction (herinafter, referred to as “PCR”) for DNA amplification, which became the foundation for the rapid development of genetic engineering, has been frequently used as an essential step in both biological research and diagnostic fields (Sec U.S. Pat. No. 4,683,195). Conventional methods for isolating nucleic acids generally involve organic solvents such as phenol and chloroform. Further, several methods have been proposed using materials that have the property of binding nucleic acids. Concrete examples of these materials are silica, glass fibers, anion exchange resins and modified magnetic beads.
The methods using these materials have advantages in that no harmful organic solvents are involved, that physical and biochemical degradation of nucleic acids during the isolation process is minimized, and that immobilized nucleic acids are less susceptible to digestion by nucleic acid-degrading enzymes. The aforementioned methods, however, still need intensive manual pipetting steps to transfer the solid materials to other vessels or containers. Thus, there is a problem in that the operator is vulnerable to potential viral and bacterial infection if infected blood or bacteria is the starting material of nucleic acid isolation.
In order to solve these problems, eliminate experimental errors due to manual operation and obtain more reliable measurement results, several automatic machines such as “MagNa Pure LC” (Roche, Switzerland) were developed to perform a large number of sample manipulations based on the concept disclosed in U.S. Pat. No. 3.985.649. Most of these automatic machines utilize magnetic beads lo eliminate the use of harmful chemical solvents and centrifugation steps when collecting nucleic acids or biological materials from various biological samples. Although these large automatic machines are adequate for high throughput isolation of the nucleic acids or biological materials, they care also bulky, expensive, rather complicated, and inefficient for a small or medium number of sample manipulations. As a result, these machines are not practical for most diagnostic clinical and small research laboratories.
Further, small and medium automatic machines such as “KingFisher” (Thermo Labsystems, Massachusetts, USA) and SX-6G (PSS, Chiba, Japan), designed for processing a relatively small amount of samples have been recently developed. These automatic machines have been designed in such a manner that a total amount of samples can be processed when performing sample measurement or processing operations, however, there is still another problem ill that they are not yet efficient for measurement of only a predetermined number of samples. That is, there is still a need for a small and portable automatic machine capable of selectively processing the necessary number of samples if necessary.